Ignition means



May 6, 1941. R. H. STONE 2,240,632

IGNITION MEANS Filed June 11, 1938 Z-Sheeis-Sheet 1 INVENTOR.

BY i

M ATTORNEY.

2 Sheets-Sheet 2 FIG 5 6 If P nl u/ G I 4. x F m a m T 3 v JHPI x U 1 hr I I 0 P h M w P It I Wm M W 7 G x w x II I. x 0 F T x 0 o 0 4. x v 4 4 IN VENTOR. 62 6274'. M

ATTORNEY.

Patented May 6, 1941 IGNITION MEANS R. Harry Stone, Bound Brook, N. J., assignor to Titeflex Metal Hose 00., a corporation of New Jersey Application June 11, 1938, Serial No. 213,230

16 Claims.

This invention relates to an internal combustion engine, especially to an ignition system for such an engine, and more particularly to an ignition system in which each cylinder of the engine is provided with one or a plurality of spark plugs.

In conventional ignition systems of this genera1 character, where a magneto energizes a distributor common to several individual spark plug circuits each of which comprises a separate insulated conductor running to its plug from its individual terminal in said distributor, and a common rotating member in the distributor is connected in series with the output terminal of the magneto being grounded to the engine block; and the plugs being usually grounded to the engine block likewise; :there is a complexity of loosely extending conductors which interferes with ready access to the engine and constitutes at least an inefficient, unreliable and unsatisfactory expedient for the intended purpose.

Among other inconveniences, the loose conductors are subjected to frequent unintended displacement and to destruction of their insulation by heat, abrasion, or forcible contact with tools; and they are always likely to be connected up improperly by persons unfamiliar with the characteristics of an ignition system. Such an exposed arrangement of the spark plug leads lends itself also to intentional disablement of a car, since the distributor can be readily displaced or dismembered, and the ignition system incapacitated, thus putting the engine out of commission.

With the addition of each set of spark plugs,

as for example in the use of a dual ignition system, the complex of conductors becomes an intolerable tangle, particularly in the case of a multi-cylinder radial type of engines used in aviation, where the disadvantages of loose conductors aggravates the problem of radio shielding.

Under such conditions an object of the present invention is to provide an improved ignition system free from loose conductors and from the disadvantages attendant thereupon, as above briefly summarized.

Another object is to provide a multi-cylinder internal combustion engine with an ignition system mechanism comprising a. source of electric current; a main conductor extended therefrom within a part of the supporting structure on which the cylinders are supported, and extended past the cylinders and their spark plugs; also to provide an individual conductor extended from each plug within a part of the supporting structure, through a short path to an individual contact terminal in the vicinity of the main conductor; and a movable means adapted to connect each of said individual conductor contact terminals in periodic succession with a complemental individual contact terminal or portion of said main conductor.

Stated in different terms, the general object of the invention is to efiect a shortening of the branch spark plug connections by localizing them in the vicinity of their respective plugs, and a cognate object of the invention is to provide for localizing the high-tension portions of an ignition system in the vicinity of each spark plug, instead of transmitting current of suitably high sparking voltage over a large number of conductors of considerablelength, and exposed to disturbance in the manner already mentioned, according to existing practice.

To carry the last-mentioned object of the invention into eifect, the invention provides for including in each of the individual sprark plug circuits a transformer, to the primary of which a low voltage current is supplied from a central generator preferably through a main conductor common to all of the individual sparking circuits; in each of which sparking circuits is included a transformer secondary adapted to deliver to each relatively short spark plug circuit a sparkling current of adequate voltage.

Other and ancillary objects and features of the invention will appear as the description of the particular physical embodiment selected to illustrate the invention progresses.

In the accompanying drawings, like characters of reference have been applied to corresponding parts throughout the several views which make up the drawings, in which:

Fig. 1 is a view in front elevation of a radial type internal combustion engine provided with an ignition system in .the construction of which the present invention has been embodied;

Fig. 2 is a fragmentary detail view, on an enlarged scale, of one of the cylinder heads shown in Fig. 1, with its associated valve stem guides;

Fig. 3 is a fragmentary detail view, in vertical section, taken on the line 3-3 of Fig. 2;

Fig. 4 is a view similar to Fig. 3, on an enlarged scale;

Fig. 5 is a view in side elevation, partly in section, of an internal combustion engine of the straight row type provided with an ignition system in the construction of which the present invention has been embodied;

Fig. 6 is a view in vertical section, taken on the line 66 of Fig.

Fig. 7 is a view similar to Fig. 6 on a larger scale;

Fig. 8 is a schematic view of the working circult of an ignition system, according to the invention, of the apparatus of Figs. 5, 6 and 7.

In a now-preferred embodiment of the invention selected for illustration and description, and referring to Figs. 1, 2 and 3, the radial cylinder aviation type internal combustion engine therein illustrated is designated generally by the reference character E and is shown as having eight cylinders, numbered II to l8 serially; the number and disposition of the cylinders being immaterial, however.

The central supporting structure S on which the cylinders and their associated conventional valve-stem-guide pipes I 9 and are mounted radially with respect to the common main shaft A, may be of any suitable construction and is illustrated as of known form.

A source of current C is indicated diagrammatically as a magneto, mounted on a bracket B and may be driven by a conventional or other suitable connection (not shown) with a moving part of the engine, such as the main shaft.

In pursuance of the present invention, a main conductor I0 leads from the current source, as at 9 in Fig. 1, through a metal conduit which connects with an arcuate metal sheath or conduit M that constitutes a substantially circular manifold running past all of the cylinders in the vicinity of the spark plugs P therein.

The main conductor i0 is embedded in a suitable mass of insulation I within the manifold M and the same reference character I is applied to insulation wherever utilized within the system.

Referring to Figs. 3 and 4, it will be seen that a branch I [IX of the main conductor I0 is led into a counter tube 2'1 of metal and filled with insulation except for an axial bore 2 la: in which is movable longitudinally a stem 3| adapted to complete .the connection periodically between the main conductor H) at a position I Ill thereof which may be considered as a local contact terminal or portion of the main conductor l0.

The stem 3| is constantly in clectro-conductive relation with the spark plug P which it serves by a branch conductor 4lextended through a short U-shaped metal sheath or conduit N having end flanges 40 engaged by coupling caps 401: which secure the branch N to threaded nipples 3la: of which one is formed integrally with a substantially conventional radio-shielding cam P surrounding the spark plug P; while the other nipple 3la: is formed integrally with a hollow post Pat in which the spindle 3| works, and which is made a part of the supporting structure of theengine as a whole.

The bore 2la: within this post has an enlarge ment 32 adapted to accommodate a spring '33 coiled around the shank of the spindle and having a fiat terminal coil '34 at its upper end and a like coil 35 at its lower end.

The coil 34 is in constant electrical contact with i a disk 36 connected electrically to the conductor 4|, while the coil 35 is similarly maintained bv the spring 33 in electrical contact with the for flange 31 of the stem 3 l, and as the coil 33 is confined between the shoulder 38 of the insulation and the foot 31 of the stem, it tends to bias constantly the stem 3| away from the conductor contact terminal H0.

held open in the yielding action of its spring 33, the periodic completion of any particular plug circuit will be accomplished by the action of suitable means associated with the working parts within the engine casing S.

As an example of such provision, a device is provided movable with a. plunger 56, which traverses hole 51 in a cap 58 screwed upon and closing the lower end of hollow post Px, the lower end of the last-mentioned plunger being disposed suitable to be operated by a motor-actuated means, such as a cam (not shown) which rotates when so actuated by working parts of the engine to which it is connected.

When the stem 3| is moved upwardly, its pointed end 39 makes good electrical contact with the corresponding contact surface I In in the branch Illa: of the main conductor ill, from which sparking current is conducted to the spark plug P along a path which is traced through the stem 3|, its foot 31, the spring 33, coil 34, contact terminal disk 36, spark plug lead 4| contact terminal 361:, and spring 42 to the spark plug P and thence ground (the cylinder block) to the magneto C which also has a ground connection as hereinbefore pointed out. The foot I is insulated from its operating means by a washer or block 55 of insulation.

From the foregoing disclosure it will be readily understood that no conductor is exposed to deleterious influences throughout the novel ignition system provided in pursuance of the present invention, all parts being thoroughly protected both against extraneous causes of impairment and against emission of an electrical field likely to interfere with radio communication with or from the plane.

The branch I01: of the main conductor I0 is likewise shielded, as shown by the short nipple 43 and coupling 44, screwed thereon and upon a threaded outlet nozzle 45 provided around an orifice in the wall of the manifold M.

In Figs. 5 to 7 inclusive I have shown the invention as applied in a modified embodiment to an internal explosion engine in which the cylinders are formed in a straight row within a supporting structure S which is indicated as an engine block of conventional form, containing six cylinders, not illustrated, in detail, their number and particular physical structure not being important. I

The reference characters P3 designate the spark plugs for these cylinders, and Ma: designates a tubular metal manifold lined with insulation and connected physically with and forming a unitary fixed structure with the engine block S. Such connection may be provided in any suitable fashion, and is shown as so provided by a stout pillar S" screwed into a boss 54 of the engine block, and

Each spark plug circuit being thus normally into a collar 53 encircling the manifold Mx.

Further support and stability is provided for the said manifold by the six branch conduits N" which are identical with the structure illustrated and described already Withreference to parts similarly identified by the same reference characters in Figs. 2 and 3, so that the description of such parts will not be repeated.

Instead of the fixed main conductor 10 provided and described with reference to the structure of Figs. 1 and 3, provision is made,-in the instan e of the modification shown in Figs. 5 and 6, of a main conductor 10, covered by a sleeve of insulation I, through which extend radially branches llll of the main conductor, there being one of these for each of the spark plug circuits.

Enlargements I" of the insulating sleeve 1' are provided, each forming a collar to receive its branch or contact terminal IN, and anti-friction bearings B (see Fig. 5), are provided at suitable intervals within which the insulated conductor I rotates as a slender shaft. It may be rotated by an electrical motor C" mounted on a bracket Se and mechanically connected with the shaft conductor I00 by a flexible insulating coupling I03. The motor may serve also to enclose a generator G which is driven by the electric motor. The generator serves to furnish current to activate the spark plugs P3 respectively and in periodic succession. Any other suitable means, driven from the moving parts of the engine if desired, may be provided for driving the ignition generator G and the shaft-conductor I00.

The current supplied by the generator may be of any suitable voltage, but in pursuance of an important feature of the invention, provision is made preferably of the novel arrangements illustrated in Fig. 7 and diagrammatically in Fig. 8, these arrangements being devised to carry out the localization of the relatively high-voltage sparking current at the region of each spark plug.

For this purpose a transformer, designated generally by the reference character T is interposed in each electrical sparking circuit, and the primary coil T of such transformer may be impressed with a current of low voltage by means of a conductor 61 leading from one terminal of the generator G as indicated in Fig.- 8 (the other terminal being grounded), this conductor passing through the metal elbow I05, shown in Fig. 5, to a contact brush in the box I06, such contact brush being in sliding electrical contact with the conductor shaft I00 which thus receives its supply of current of low voltage through the commutator brush. The conductor I00 passes through the manifold M11, as indicated, with branches at the region of the respective spark plugs as indicated at IOI in Fig. '7. A conductor I06 leads from a contact terminal I36 (engaged by contact stud IOI) to one terminal of the primary coil T and whenever the rotation of shaft I00 swings the outer end of stud I0l around into registry with the contact terminal I36, the energizing low voltage current from generator C" flows through the path traced by 62, I00, IOI, I36, I08', primary T to ground on the transformer casing.

The secondary coil T" of the transformer may be designed desirably to furnish a high voltage sparking current, and nected to a lead 4 I a: to the spark plug Pa, theother terminal being connected to ground on the transformer casing, as shown in Fig. 7, and also indicated clearly in Fig. 8, the grounding being preferably to n plugs also are grounded, preferably in known fashion.

From the foregoing it will be seen that the high tension sparking current is localized at each spark plug, within a working circuit of very short length, and is so confined that it has no opportunity to wander, nor does it exercise any unfavorable static action on the radio of a plane for example, being completely radio shielded.

The arrangements of Fig. I may be readily provided in connection with the modification of Fig. 4, so far as the interposition of a transformer into the sparlnng circuit is concerned, and it will be clear that any desired number of spark plug circuits may be provided corresponding to the plugs used in any number of cylinders, and that the engine block, to which the spark.

one of its terminals is conductor extended within these may be one, two, three or more plugs used in each cylinder.

What I claim is:

1. In an lntemal combustion engine having a plurality of cylinders each provided with at least one spark plug and a common supporting structure therefor: an ignition system mechanism comprising a source of electric current; a main conductor extended therefrom within a part of said supporting structure, past a plurality of said cylinders and spark plugs; an individual conductor extended within a part of said supporting structure from each plug to a contact terminal in the vicinity of said main conductor; and movable means, corresponding to each cylinder and distributed along said main conductor, adapted to connect each of said individual conductor contact terminals in periodic succession with a complemental individual contact portion of said main conductor, a housing encasing said main conductor and said contact terminals, 9. housing for each of said spark plugs and a conduit for each of said individual conductors, each of said conduits being separate from said housings but removably secured thereto. 7

2. In an internal combustion engine having a plurality of cylinders each provided with at least one spark plug and a common supporting structure therefor: nism comprising a source of electric current; a main conductor extended therefrom within a part of said supporting structure, past a plurality of said cylinders and spark plugs; an individual conductor extended within a part of said supporting structure from each plug to a contact terminal in the vicinity of said main conductor; and movable means, corresponding to each cylinder and distributed along said main conductor, adapted to connect each of said individual conductor contact terminals in periodic succession with a complemental individual contact portion of said main conductor, said movable means being constituted by a.rotatable conductor shaft having contact terminals spaced serially along its length and each adapted to serve a spark plug contact, a housing encasing said main conductor and said contact terminals, 9. housing for each of said spark plugs and said individual conductors, each of said conduits being separate from said housings but removabli secured thereto.

a 3. In an internal combustion engine having a plurality of cylinders one spark plug and a common supporting structure therefor: an ignition system mechanism comprising a source of electric current; a main conductor extended therefrom within a part of said supporting structure, past a plurality of said cylinders and spark plugs; an individual conplug to a contact terminal said main conductor; and

structm'e from each in the vicinity of movable means, corresponding to each cylinder and distributed along said main conductor, adapted to connect each of said individual conductor contact terminals in .periodic succession with a. complemental individual contact portion of said main conductor, said movable means being constituted by a rotatable conductor shaft having contact terminals spaced serially along its length and each adapted to serve a spark plug contact and means to rotate said shaft, 9. housing encasing said main conductor and said contact terminals, a housing for each of said spark plugs and a conduit for each of said individual conan ignition system mecha-' a conduit for each of each provided with at least a part of said supporting.

one spark plug and a common supporting structure therefor; an ignition system mechanism comprising a source of electric current; a main conductor extended therefrom within a part of said supporting structure, past a plurality of said cylinders and spark plugs; an individual conductor extended within a part of said supporting structure from each plug to a contact terminal in the vicinity of said main conductor; and movable means, corresponding to each cylinder and distributed along said main conductor, adapted to connect each of said individual conductor contact terminals in periodic succession with a complemental individual contact portion of said main conductor, said movable means being constituted by a rotatable conductor shaft having contact terminals spaced serially along its length and each adapted to serve a spark plug contact; and a motor to drive said shaft separately, a housing encasing said main conductor and said contact terminals, a housing for each of said spark plugs and a conduit for each of said individual conductors, each of said conduits being separate from said housings but removably secured thereto.

5. In an internal combustion engine having a plurality of cylinders each provided with at least one spark plug, and a common supporting structure therefor: an ignition system mechanism comprising a source of electric current; a main conductor extended therefrom within a part of said supporting structure, past a plurality of said cylinders and spark plugs; an individual conductor extended within a part of said supporting structure from each plug to a contact terminal in the vicinity of said conductor; and movable means, corresponding to each cylinder and distributed along said main conductor,

adapted to connect each of said individual conductor contact terminals in periodic succession with a complemental individual contact terminal of said main conductor; said movable means being constituted by a conductor shaft having an insulating sleeve and radial contact studs adapted to be engaged serially with said individual conductor contact terminals as the shaft rotates, a housing encasing said main conductor and said contact terminals, a housing for each of said spark plugs and a conduit for each of said individual conductors, each of said conduits being separate from said housings but removably secured thereto.

6. In an internal combustion engine having a plurality of cylinderseach provided with at least one spark plug, and a common supporting structure therefor: an ignition system mechanism comprising a source of electric current, including a magneto; a main conductor extended therefrom within' a part of said supporting structure,

. past a plurality of said cylinders and spark plugs; an individual conductor extended within a part 9,240,632 ductors, each of said conduits being separate having an insulating sleeve and radial contac studs adapted to be engaged serially with saic individual conductor contact terminals as th! shaft rotates and a motor to rotate said shaft a housing encasing said main conductor and said contact terminals, 2. housing for 'each 01 said spark plugs and a conduit for each of said individual conductors, each of said conduit: being separate from said housings but removably secured thereto.

7. In an internal combustion engine having a plurality of cylinders each provided with at least one spark plug, and a common supporting structure therefor: an ignition system mechanism comprising a source of electric current; a main conductor extended therefrom within a part of said supporting structure, past a plurality of said cylinders and spark plugs; an individual conductor extended within a part of said supporting structure from each plug to a contact terminal in the vicinity of said main conductor; and a reciprocating cam-controlled means adapted to connect each of said individual conductor contact terminals in periodic succession with a complemental individual contact portion of said main conductor.

8. An ignition system for an internal combustion engine having the features claimed in claim '7, in which each of said cam-controlled devices includes a stem reciprocable in a socket formed in the supporting structure and having one end adapted to make and break contact with a part of said main conductor and a spring coiled around said stem within the socket and adapted to bias said stem to circuit-breaking position.

9. An ignition system of an internal combustion engine having the features claimed in claim '7, in which each of said cam-controlled devices includes a stem reciprocable in a socket. formed in the supporting structure and having one end adapted to make and break contact with a part of said main conductor and a spring coiled around said stem within the socket and adapted to bias said stem to circuit-breaking position,

said spring adapted to serve in part at least to maintain said stem and one of said individual contact terminals in constant electro-conductive relation.

10. In an internal combustion engine having a plurality of cylinders each provided with at least one spark plug, and a common supporting structure therefor: an ignition system mechanism comprising a source of alternating electric current; a main conductor extended therefrom within a part of said supporting structure, past a plurality of said cylinders and spark plugs; .an individual working circuit for each plug including a transformer having a primary and secondary within a part of said supporting structure including an individual contact terminal in the vicinity of said main conductor; and also including a transformer having a primary and secondary for each plug, and movable means, corresponding to each cylinder and distributed along said main conductor, adapted to connect each of said transformer primaries in periodic succession with a complemental individual contact terminal of said main conductor to activate said primaries serially.

' 11. In an internal combustion engine having a plurality of cylinders each provided with at least one spark plug, and a common supporting structure therefor; an ignition system mechanism comprising a source of alternating electric current; .a main conductor extended therefrom within a part of said supporting structure, past a plurality of said cylinders and spark pluigs; an individual working circuit for each plug including a transformer having a primary and secondary within a part of said supporting structure including an individual contact terminal in the vicinity of said main conductor; and also including a transformer having a primary and secondary for each plug, and movable means, corresponding to each cylinder and distributed along said main conductor, adapted to connect each of said transformer primaries in periodic succession with a complemental individual contact terminal of said main conductor to activate said primaries serially, each secondary being included in an individual sparking circuit with its spark plug.

12. In an internal combustion engine having a plurality of cylinders each provided with at least one spark plug, and a common supporting structure therefort an ignition system mechanism comprising a source of electric current; a main conductor extended therefrom within and insulated from, a metal conduit or sheath conmeans corresponding to each of said cylinders and distributed along said main conductor for connecting the said contact terminals with said main conductor in periodic succession, a housing for each of said spark plugs, each of said con- 7 duits for said individual conductors being separate from the first mentioned metal conduit or sheath and said spark plug housing, but removably secured to the last mentioned conduit and to said housing.

13. The combination with the spark plug of an internal combustion engine,- of a radio shielding casing therefor, an ignition conductor detachably contacting said spark plug and a radio shielding conduit for said conductor comprising an elbow separate from but detachably secured to said spark plug casing and a second elbow at the other end of said conduit.

14. The combination with the spark plug of an internal combustion engine, of a radio shielding casing therefor, an ignition conductor detachably contacting said spark plug and a radio shielding conduit for said conductor comprising an elbow separate from but detachable secured to said spark plug casing and a second elbow at the other end of said conduit, said elbows being integral with said conduit.

15. The combination with a plurality of spark plugs, of radio shielding housing common to conducting means for said spark plugs, conducting means in said housing, a radio shielding casing for each of said spark plugs, individual radio shielding conduits each detachably secured to said housing and also detachably secured to said casing, each of said conduits comprising an elbow adjacent the spark plug casing and a second elbow at the other end of the conduit. said elbows being integral with the conduit, and an ignition conductor extending through each of said conduits and detachaibiy connected with a spark plug and also with said conducting means.

16. The combination with a plurality of spark plugs, of radio shielding housing common to conducting means for said spark plugs, conducting means in said housing, a radio shielding casing for each of said spark plugs, individual radio shielding conduits each detachably secured to said housing and also detachably secured to said casing, each of said conduits comprising elbows one adjacent the spark plug casing and another adjacent said housing and an ignition conductor extending through each of said conduits and detachably connected with a spark plug and also with said conducting means.

. R. HARRY STONE. 

